Desk telephone



Aug. 23, 1938. H. F. OBERGFELL DESK TELEPHONE 2 Sheets-Sheet 1 Original Filed Dec: 21, 1934 FIG. 2

INVENTOR. HERBERT F. OBERGFELL ATTORNEY.

Aug- 23, 1938- H. F. OBEZGFELL 2,127,569

DESK TELEPHONE I Original Filed Dec. 21, 1954 2Sheets-Sheet 2 V Flags I N VEN TOR.

HERBERT F. OBERGFELL Patented Aug. 23, 1938 znrstt DESK TELEPHONE v Herbert F. obergfell, River Forest, 111., assignor' to Associated Electric Laboratories, Inc., Chi-' cago, Ill., a corporation of Delaware Original application December 21,1934, Serial No.

Patent No. 2,074,415; dated March 23,

1937. Divided and this application'November 1, 1935, Serial No. 47,864

2 Claims.

This invention relates in general to telephone sets but more particularly to an improved desk telephone set of the self-contained type, and the principal object of the invention is to provide a desk telephone set in which all of the apparatus associated with a subscribers substation telephone set is contained in a single unit.

A further object of the invention is to arrange all of the parts within the telephone set so that they are easily accessible for inspection, repair or adjustment. A further object is to provide a casing in which standard pieces of telephone apparatus may be used, and in arranging these pieces of apparatus within the telephone casing to use the least possible space with the best advantage. I

A further feature resides in the arrangement of the various pieces of telephone apparatus in the case of the desk telephone in such a manner as to utilize all of the existing space on the base Without interfering with other pieces of apparatus either on the base or that mounted upon the cover. Similarly the apparatus mounted on the cover or top portion of the telephone is arranged to utilize a minimum amount of space and so as not tointerfere with the apparatus mounted on the base portion.

A particular feature of the invention resides in the novel operating arrangement and support for the switching contacts in combination with the supporting arrangement for the ringing push button and associated contacts.

This application is a division of a parent application filed December 21, 1934, Serial No. 758,577, reference to which may be had for a more detailed description of the features not specifically described or claimed in the present application.

Other objects and features not enumerated will be pointed out more in detail in connection with the detailed description which, together with the accompanying two sheets of drawings, illustrates in detail a preferred embodiment of the desk telephone set constituting the invention.

Referring to the drawings, Fig. 1 illustrates in perspective the general appearance of the desk telephone; Fig. 2 is a cross sectional View along the line 2-2 of Fig. 1; Fig. 3 is an underside view of the cover illustrating the arrangement of the apparatus therein; Fig. 4 is a plan view of the base of the desk telephone showing the arrangement of the apparatus thereon;-Fig. 5 is a perspective view of the cord holder; while Fig. 6 is a slightly fragmentary cross-sectional view along the line 5-6 of Fig. 1 illustrating the switching and push button contact operating arrangement and support.

Referring now more particularly'to Fig. 1, the cover portion of the desk telephone indicated as '5 is formed of some suitable plastic insulating compound which lends itself well to molding so that all the parts may be formed 'into the desirable shape; This cover is formed generally in the shape of a truncated pyramid having a sloping front upon which the calling device l is mounted, i

a set of pillars 8 are formed in the cover 5 between which the usual well known combination transmitter receiver handset is supported in its normal position in contact with the switching button 9 protruding midway between the pillars 8. Slightly forward of the switching button 9 and between the front pair of pillars 8a ringing button it! is arranged.

The base portion 6 is removably secured to the cover 5 and in the well known manner serves as a support for the usual telephone instrumentalities such as ri nger coils 2!? and associated gongs 2|, inductioncoil 30, terminal blocks SI and 32, and the condenser 36.

Referring now more particularly to Fig. 6 as Well as Fig. 3, the switch operating mechanism will be described. This mechanism is mounted on, the inside center of the cover 5 and comprises a supporting bracket lil secured to the inside of the cover by means of screws E6 on each end of the bracket. The plunger 9 which is actuated by the removal and replacement of the handset on the top of the telephone between the pillars 8, extends through an opening in the cover 5 and the bracket Hi to engage the operating lever H which is pivoted to the bracket lfil by pivot 12.

The downward movement of the lever H by plunger 9 is limited by the stop 13 formed out of bracket it. The lever H has a pair of bushings mounted on it adjacent to pivot '12 which engage and operate the sets of contact springs 14 and 15 to control the electrical switching operations of the telephone. By the depression of the plunger 9 when the handset is on the cradle, the lever l! is moved downward and through the medium of the bushings on the lever the contact springs l4 and 15 are operated. The removal of the handset permits the plunger 9 to move upward and the lever ll to follow it and due to the tension stored in the armature springs of contacts 14 and l5 suflicient tension is imparted to the lever ll to hold the plunger 9 in its uppermost position without the necessity of providing additional coil springs or other restoring tension members. The contact spring sets 14 and 15 are held in' position between insulated spacers by means of screws threaded into brackets formed in the supporting bracket 10. A bracket 18 is attached by screws to the supporting bracket 10 and this bracket supports at an angle the set of contact springs 11 which are operated by the ringing push button [0 extending to the outside of the cover 5. The purpose of this push-button is so that the person at the telephone set may by suitably manipulating the button It] signal another party 0n the telephone line by means of a code. The switch operating mechanism and contact springs as well as the contact spring set of the ringing button are on the inside of the inside cover in such a manner as not to interfere with their operating and so as not to come into contact with the other pieces of apparatus mounted in the base. Likewise the wiring is so arranged that the conductors connecting the various contact spring sets do not interfere with the operation of any of the pieces of apparatus.

Referring to Figs. 3 and 4 it will be seen that when screws l2 and I3 are removed from threaded engagement with the cover 5 at and id, the cover may be lifted off the base 6 and laid upside down on top of the base. When opened up in this manner all of the apparatus on the base as well as all of the apparatus on the cover is immediately visible for inspection. Any particular piece of apparatus may be readily removed, replaced, or repaired without interfering with ad jacently mounted pieces of equipment, and the cables and cords connecting the base with the cover and those entering the cover from the outside are protected in such a manner that they do not become entangled with the equipment or obstruct it in any manner. The individual wires connecting the contact springs of the switching members and certain other pieces of apparatus on the base have not been shown entirely in order that the equipment may be more clearly illustrated and only short broken 011 connections extending from the terminals and the cords have been shown. It will be understood, of course, that for different types of circuits the wiring of the telephone will be changed from that shown, although such changes will not necessarily in clude additional conductors in the cord or cable.

Having described the invention, whatis considered to be novel is pointed out in the appended claims.

What is claimed is:

1. In a telephone desk set, a switching member mounted thereon, a bracket mounted onthe inside of said desk set, a lever pivoted to said bracket and operated by said switching member, switching springs supported on said bracket and operated by said lever into one position for a certain movement of said switching member and into another position for a different movement of said switching member, a stop on said bracket for limiting the movement of said lever by the downward movement of said plunger, a ringing button on said telephone set, and a set of contact springs supported on said bracket and directly operable by said ringing button.

2. In a telephone desk set having a cradle formed on the top thereof supporting a handset, a bracket secured to the under side of said cradle, a lever pivoted on one end of and below said bracket, contact springs extending below said lever and mounted on said bracket, bushings attached to the pivoted end of said lever and in operative relation to said contact springs, a plunger extending through said cradle, said handset normally holding said plunger pressed against the end of said lever and said bushings holding said contact springs in their normal open position, the removal of said handset causing the tension in said springs to move said plunger upward and to rotate said lever and to close said contact springs, a stop member on said bracket limiting the downward movement of said plunger, a second set of contact springs supported on said bracket, and a second plunger resting against the end of said contact springs and extending through the cradle top of the desk set but in a position not engageable by said handset.

HERBERT F. OBERGFELL. 

